Vehicle seats with a seat depth adjustment device are already known in various embodiments. At least in most configurations of this type, the region of the seat surface located in the direction of travel, which extends forwards in particular transversely to the backrest which is usually present, is varied with regard to its size in order thus to allow an adaptation to different drivers' requirements or to different anatomies of the drivers. Of course, the need for such adjustment may be characterized not only by the anatomy of the driver but also by further factors, such as for example the sense of comfort of the driver or the like.
DE 101 12 918 A1 discloses that in the case of vehicle seats with seat depth adjustment, there is no problem in terms of an annoying gap in the region of the seat surface. In order to counteract such a gap formation, DE 101 12 918 A1 proposes that the vehicle seat has a seat depth adjustment part which is covered with a pad material, wherein this pad material is guided in the adjustment direction by an adjustment part with twice the adjustment compared to the adjustment travel of the seat depth adjustment part, and wherein this guidance takes place by means of a guide device which consists of an entrained rack-and-pinion guide.
DE 41 04 697 C2 discloses a vehicle seat with adjustable seat depth, in which an intermediate element is provided for bridging over the gap or the intermediate space between a rear and a front section of the seat pad, which intermediate element comprises two identical pairs of intersecting arms of equal length which intersect half-way along their length and are pivotably mounted there on an axle running in the transverse direction of the seat.
DE 41 14 735 A1 discloses a vehicle seat with adjustable seat depth, in which the upholstery material which covers a shell on the outside can be deflected by means of a winding shaft guided in a spring-loaded manner along rails in order to extend and shorten the seat. The shaft is arranged here in the region of the front end of the seat surface and below the latter.
DE-PS-1099866 discloses a vehicle seat in which a leg support is continuously adjustable in the longitudinal direction.
DE 199 423 51 B4 discloses a vehicle seat with a seat depth adjustment device, in which a base support provided with a triangular cross section is mounted at one corner, wherein a drive unit with a longitudinally displaceable push rod for seat depth adjustment acts in the region of a further corner of the base support, eccentrically with respect to the bearing of the base support. Here, the seat surface is covered by upholstery covering which is pulled around the front adjustment section and is extended by a rubber band.
DE 41 04 440 C2 discloses a vehicle seat with seat depth adjustment, in which the seat pad has a front part and a rear part, wherein the front part and the rear part of the pad form a coherent, continuous seat pad surface at any seat depth setting of the seat pad.
Further examples of known vehicle seats with seat depth adjustment are known from DE 41 04 409 C2 or DE 196 45 772 A1 or DE 198 01 893 C2 or DE 197 40 045 A1.
Accordingly, the present invention is directed to providing a vehicle seat with adjustable seat depth in which the seat depth adjustment can be carried out in an operationally reliable and simple manner.